Sains Malaysiana 43(4)(2014): 595–601

Kesan Masa Pengendapan dan Saiz Elektrod Lawan dalam

Penghasilan Katod Komposit LSCF-SDC Karbonat untuk SOFC

(Effects of Deposition Time and Counter-electrode Size on the Fabrication of LSCF-SDC Carbonate Composite Cathode for SOFC)

NURUL AKIDAH BAHARUDDIN, HAMIMAH ABD. RAHMAN, ANDANASTUTI MUCHTAR*,

ABU BAKAR SULONG & HUDA ABDULLAH

Institut Sel Fuel, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan

Malaysia

Received: 29 October 2012/Accepted: 15 July 2013

ABSTRAK

Penggunaan proses pengendapan elektroforetik (EPD) telah menunjukkan potensi yang memberangsangkan dalam pembangunan komponen katod untuk sel tunggal sel fuel oksida pepejal (SOFC). Sehubungan itu, kesan saiz elektrod lawan dan masa pengendapan terhadap ketebalan dan kualiti filem komposit katod LSCF-SDC karbonat pada substrat seria terdop samarium (SDC) karbonat telah dikaji untuk membuktikan kebolehlaksanaan kaedah ini. Kesan perubahan parameter tersebut terhadap penghasilan filem LSCF-SDC karbonat dikenal pasti dengan menetapkan nilai pH ampaian dan voltan kenaan. Parameter masa pengendapan diubah suai dengan lima masa yang berbeza iaitu antara 10 - 30 min, manakala dua saiz elektrod lawan yang digunakan ialah 25 × 25 mm² dan 50 × 50 mm². Filem komposit katod kemudian disinter pada suhu 600^oC selama 90 min. Pencirian mikrostruktur dan ketebalan filem LSCF ini diperoleh menggunakan mikroskop imbasan elektron (SEM). Penggunaan saiz elektrod lawan yang besar (50 × 50 mm²) didapati mampu menghasilkan filem komposit katod yang lebih tebal. Selain itu, kesan perubahan parameter (masa pengendapan dan saiz jaring elektrod lawan) dikenal pasti melalui analisis berat dan ketebalan filem LSCF-SDC karbonat. Filem katod berketebalan 4.6 - 30.8 μm telah berjaya diendap pada tempoh pengendapan yang digunakan. Ketebalan katod komposit LSCF-SDC karbonat yang diperoleh berada dalam julat ketebalan yang telah dihasilkan oleh pengkaji terdahulu melalui kaedah pembentukan yang sama ke atas bahan katod lain. Keputusan kajian menunjukkan bahawa kaedah pengendapan elektroforetik bagi pembentukan katod komposit amat berpotensi untuk kajian yang lebih intensif.

Kata kunci: Elektrod lawan; LSCF-SDC karbonat; masa pengendapan; pengendapan elektroforetik (EPD)

ABSTRACT

The electrophoretic deposition (EPD) process has shown great potential in the development of cathodes for solid oxide fuel cell (SOFC). This study thus aimed to determine the feasibility of the electrophoretic deposition technique in producing composite cathode films. Two parameters were investigated, namely, the effects of counter electrode size and those of deposition time on the thickness and quality of an LSCF-SDC carbonate cathode composite deposited onto an SDC carbonate substrate. The effects of the changed parameters were observed by applying constant suspension pH and voltage. Five different deposition times ranging from 10 to 30 min were selected. The counter electrode sizes used were 25 × 25 mm² and 50 × 50 mm². Then, the cathode composite films were sintered at 600°C for 90 min. Microstructural characterization and film thickness measurement were performed using a scanning electron microscope (SEM). The 50 × 50 mm² counter electrode was found to produce a cathode composite film with higher thickness. The effects of the selected parameters (deposition time and counter electrode size) were also determined by analyzing the weight and thickness of the obtained LSCF-SDC carbonate films. The results showed that for the selected time interval, a film thickness of 4.6 to 30.8 μm is generated. Further studies on fabricating LSCF-SDC carbonate cathode composites by electrophoretic deposition present promising potential given that the film thickness obtained agree well with those derived in previous studies on various types of cathode materials.

Keywords: Counter electrode; deposition time; electrophoretic deposition (EPD); LSCF-SDC carbonate

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*Corresponding author; email: muchtar@eng.ukm.my